Well this game isnt that hard actually, the only option I would need is unlimited ammo, so maybe there is a console command line for that cheat.

EDIT:

regarding the auto saving at checkpoints... I recieved a few of these during play and I thought "great" untill ofcourse I quit the game and came back later only to find out there is no 'LOAD' option and choosing the 'Select Chapters' option and select the chapter you got to only makes you play that chapter from the beginning which in my case I was still on capter 1 and I was on the dock level hacking into the camera system looking for some guy at the opera.

I agree its stupid to have any single player mode restricted from cheats or trainers!Why would anyone care if you beat the computer with an game aid.If that upsets anyone they really need to get out more.

i spent about 2 hours today looking at this situation with xlive and to no avail. the xlive .dll is so completely embedded into the game code that you cannot turn it off. for now my only solution is to let the game crash and alt-tab back into the game (if your system and setup allows this).

i am very sorry for this but i think anyone building a trainer for this game is going to get the same effect. i am still looking at new ways to try and defeat this, but they will be wonky at best and so i am hesitant to put out something that won't work half the time.